Conventional PC systems may include a hardware/software built-in alarm clock system using the Real Time Clock (RTC). The RTC is controlled by the OS. The latest Operating Systems (e.g. Microsoft Windows®) allow the user to setup up a wakeup interrupt from the RTC alarm to power on the system. However, this approach requires a very complicated design. For example, a separated power plane on the system board is required to allow the chipset to receive the RTC wakeup interrupt signal when the rest of the system is powered off. On the other hand, to setup the clock requires the complete system boot up process and use the complicated Operating System to do a simple setup. Also, there is no indicator on the system to tell the current time or that the alarm is turned on.